What is the primary function of the CPU?

• A. Stores data permanently
• B. Manages network connections
• C. Displays video output
• D. Executes instructions and controls the operation of the computer

Answer: (D)

The CPU’s main job is to execute instructions and coordinate the computer’s activities. It fetches program instructions from memory, decodes what those instructions mean, and acts on them, performing calculations, making decisions, and sending control signals to other parts of the system. This is why the CPU is often called the brain of the computer—it drives how software runs and how data moves around the machine.

Data permanently stored on a computer lives in storage devices like hard drives or solid-state drives, not in the processor itself. Network connections are handled by network hardware and software stacks, while displaying video output is the job of the graphics subsystem or GPU. So the description that emphasizes executing instructions and controlling the operation of the computer captures the CPU’s essential role.